Inspection apparatus and means

ABSTRACT

Apparatus and means are provided for the quality control of hard shell pharmaceutical capsules comprising a set of collets or holders arranged side-by-side in a row for supporting and moving successive sets of individual capsule shells open-end foremost in timed relation from a work station, photosensor means for scanning a light beam projected across the path of the conveyed capsule parts, control means for activating the scanning mode during a predetermined time segment in the motion cycle such that during the time segment the light beam bypasses the leading edge of advancing standard-length capsule parts but is blocked and prevented from being scanned by the intervention of any overlength capsule parts, and means responsive to the scanning means for signalling and/or rejecting capsule parts thus found blocking the beam.

United States Patent [191 Kuroda et a1.

[ INSPECTION APPARATUS AND MEANS [75] Inventors: Toyoaki Kuroda, Troy,Mich.;

Toyokazu Shimizu, Sagamihara, Japan [73] Assignee: Parke, Davis &Company, Detroit,

Mich.

22 Filed: May 22, 1972 211 App]. No.: 255,766

[52]- US. Cl... 250/223 R, 209/111.7, 250/560 [51] Int. Cl. H0lj 39/12[58] Field of Search... 250/221, 222, 223 R, 223 B, 250/220 M, 219 DF,219 TH, 219 WD, 219

[ 1 June4,.1974

Keller 250/223 B Primary Examiner.1ames W. Lawrence Assistant ExaminerD.C. Nelms [5 7] 9 ABSTRACT Apparatus and means are provided for thequality control of hard shell pharmaceutical capsules compris ing a setof collets or holders arranged side-by-side in a row for supporting andmoving successive sets of individual capsule shells open-end foremost intimed relation from a work station, photosensor means for scanning alight beam projected across the path of the conveyed capsule parts,control means for activating the scanning mode during a predeterminedtime segment in the motion cyc1e such that during the time segment thelight beam bypasses the leading edge of advancing standard-lengthcapsule parts but is blocked and prevented from being scanned by theintervention of any over-length capsule parts, and means responsive tothe scanning means for signalling and/or rejecting capsule parts thusfound blocking the beam.

6 Claims, 8 Drawing Figures 1 INSPECTION APPARATUS AND MEANS SUMMARY ANDDETAILED DESCRIPTION This invention relates to apparatus and means forinspecting capsules in connection with pharmaceutical capsuleproduction. More particularly, the invention relates to apparatus andmeans for inspecting capsule shell parts. by photosensor means.

In the production of capsules by the dip-molding technic the art hasprovided apparatus for discriminating between standard-length capsuleparts and overlength capsule parts so that the latter are rejectedduring the course of normal production operations (see, for example, US.Pat. No. 3,508,647). Thus, after the dried capsule shells are strippedand cut, they are individually carried by a battery of collets to a likenumber of joiner blocks. In so doing, the capsule shells approach arejection station located in front of the joiner blocks where anyover-length shells are destroyed or dislodged from their respectivecollets by the action of rejection fingers which, at a precise point inthe transfer c'ycle, momentarily intersect the path of the leading edgesof shells just prior to their advance into the joiner blocks. Whileavailable means have been satisfactory, there has been no provision forcalling attention to the operator the occurrence of a malfunction,particularly when it occurs, or for collecting and accounting forrejected capsules.

It is therefore an object of the present invention to provide means fordetecting the presence of defective capsule parts or over-length capsuleparts being produced during the production operation. 1

It is also an object of the present invention to provide apparatus fordetecting and eliminating from the production output capsule parts whichexceed a standard predetermined length.

It is a further object of the invention to provide means for rejectingover-length capsule parts without physically contacting the rejectedparts during the detection step.

These and other objects, purposes and advantages of the invention willbe seen in the following description and'the accompanying drawing inwhich:

FIG. 1 is a top view, in part, of a capsule production machine;

FIG. 2 is a view in elevation of the capsule machine taken on line 22 ofFIG. 1;

FIGS. 3a, 3b, 3c and 3d are side views showing at different stages ofthe motion cycle the positional relationship of a capsule shell holder,21 light beam and a capsule joiner block;

FIG. 4 is a diagram of the detection system of the invention showingcam-operated switch means for indexing the detection system; and

FIG. 5 is a view ofa segment of the conveyor line and of a gatingmechanism for rejecting over-length capsules.

In a preferred form illustrated in FIGS. 1 and 3 the apparatus includesa row of joiner blocks 11 having channels Ila and 11b in conventionalform for receiving paired bodies 12 and caps 13, respectively; collets14 are provided for holding the individual capsule shells l2 and 13 andpresenting them for joining to the joiner blocks 11. The housing (FIG.2) contains a light source 21, a first reflecting mirror 22, a focussinglens 23 for projecting a light beam 24, a second reflecting mirror in asuitable mounting 25a, and a photosensor 26. The first mirror 22 has asurface which reflects and also transmits light. The housing includes ahorizontal adjustment control 31 and a vertical adjustment control 32for purposes of aligning the light beam 24 in the direction illustrated.

The apparatus also includes a conveyor extending along the length of therow of joiner blocks 11 to a receiver 41. Near the end of the conveyoris a gate 42 which reciprocates from a closed position to an openposition under action of a rotary solenoid 43. The apparatus furtherincludes means for discriminating optically between the presence ofreflected light from the mirror 25 and the absence thereof. These meansshown in FIG. 4 comprise a photosensor 26 and amplifier 27 in serieswith a cam-driven switch 28 operating from the drive cam 29 of theautomatic drive means 30. The switch 28 in turn operates in a circuitwith an alarm device 44 and/or light (not shown) and with a timer inseries with agate solenoid 43.

OPERATION In the conventional operation of making capsules by thedip-molding technic, capsule parts are stripped from the pins intosupporting collets, adjusted to length, cut while being rotated and,finally, carried by the collets to the position illustrated in FIG. I.It will be realized that the apparatus operates in the latter respect bybringing the body parts on one side of the joiner blocks and the capparts from the opposite side and that from this configuration each pairof parts is then brought together and joined in its respective joinerblock. In principle, however, the operation on the body side isequivalent to that on the cap side of the machine. For purposes ofillustration, therefore, the operation as it applies to the presentinvention will be described only with respect to the body side of themachine. For inspection purposes according to the invention, the opticalsystem is activated and set up, if necessary by adjustment of thegeometry controls 31 and 32 as indicated, so that the projected lightbeam follows the line shown in FIGS. 1 and 2. In a preferred form, thecross-section of the beam 24 is rectangular as seen in FIG. 3a where itimpinges on the mounting 25a and mirror 25 for the full height and widththereof as shown by the dotted outline of the beam. The mirror in turncorresponds in height to the width of a capsule body. The inventioncontemplates the use of detachable mountings 25a (as a covering mask forthe mirror 25) having apertures of differing dimension so that in effectthe'exposed dimension of the mirror 25 can be varied to correspond witheach different capsule size being processed, as desired.

Regarding the work flow through the machine, the beam 24 at all times,regardless of the phase of the work cycle, is projected toward themirror 25 by means of the light source 21, the reflecting mirror 22, andthe lens 23, as shown in FIGS. 2 and 3a. In the absence of obstructionin the scanning zone, the beam is reflected back from mirror 25 throughthe lens 23 and light transmitting mirror 22 to the photosensor 26. Atthe point in the work cycle when a standard-length colletheld capsulebody (FIG. 3b) is movedtoward the joiner block 11 with its leading edgejust short of the beam,- the alarm circuit is enabled by the cam 29 andswitch means 28 of FIG. 4. At this same point, however, when anover-length capsule body (FIG. 3c, over-length usually because it isuncut) is brought into the area of the light beam 24, it blocks the beamand therefore causes the photosensor 26 to send an input to the alarm 44and timer 45. The scanning mode (lasting about 0.1 second andcorresponding to the part of the motion cycle illustrated in FIGS. 3band 3c) is activated during the time the switch 28 is biased by cam 29into the on position. As soon as the cam'29 clears the switch 28, thescanning mode ceases for the balance of the collet transfer cycle (about3 seconds, corresponding in part to the motions illustrated in FIGS. 3aand 3d). Thus, when the collet l4 and ejector rod advance (FIG.

3d) through the beam 24 for transferring the'body into the joiner blockand ejecting the body joined with the cap 13 from the joiner block thealarm system is deactivated. As indicated, the system remainsdeactivated for the rest of the cycle during which the empty collet 14and ejector rod 15 retract through the beam and return to originalposition for pickup of the next capsule shell from the mold pin.

As will be understood, the capsules in any case whether standard-lengthor over-length are delivered to the joiner blocksin normal fashion andejected. They fall upon ejection to the conveyor where they are conveyedtoward the exit end of the conveyor. In normal fashion, the capsulesejected in each cycle (e.g., 30 in number) tend to aggregate together inspaced groups moving ,on the conveyor surface, illustrated in FIG. 1 asgroups A, B, C and D. [n this regard the invention in the mentionedpreferred form provides for the timer 45 to send a signal to the gatesolenoid 43 for operation in connection with the detection of light beaminterference by an over-length capsule shell. The timer is set so thatthe signal to the solenoid is delayed until the capsule group containingthe defective capsule reaches the gate 42, which delay is a function ofrate of conveyor travel. At this time the gate solenoid 43 is activatedto open the gate 42 whereupon the defective capsule group is droppedthrough the reject chute 46 to a receptacle 47. The gate then closesbefore the next succeeding capsule group arrives. In the absence of beaminterference during the scanning mode, the capsules in each groupprocessed are allowed to pass the gate 42 to the end of the conveyor andto be collected as normal capsules in the output receptacle 4].

While the invention has been illustrated in considerable detail, it willbe realized by those skilled in the art that wide variation can be madein such detail without departing from the scope of the invention ashereinafter claimed.

We claim:

1. Apparatus for the quality control of hard shell pharmaceuticalcapsules having a set of collets arranged side-by-side in a straight rowfor supporting and moving successive sets of individual capsule shellswith their open-ends forward in timed relation from a work station to'acorresponding parallel row of joiner blocks, characterized by a lightbeam projected on a line parallel to the joiner blocks across the, pathof the conveyed capsule parts, photosensor means for scanning the lightbeam, control means for activating the photosensor means during apredetermined time segment such that t the light beam bypasses theleading edge of advancing standard-length capsule parts but is blockedand prevented from being scanned by the intervention of any over-lengthcapsule parts, and means responsive to the scanning means for rejectingany set'of capsule parts thus found blocking the beam.

2. Apparatus according to claim 1 where the light beam is projected bymeans of first and second reflecting mirrors.

3. Apparatus according to claim 1 where the control means comprises anelectrical switch operated by cam means.

4. Apparatus according to claim 1 where the means responsive to thescanning means comprises a solenoiddriven gate for rejecting capsuleparts.

5. The apparatus of claim I where the rejection means responsive to thescanning means comprises time-delay signalling means.

6. Apparatus for the quality control of hard shell pharmaceuticalcapsules having a set of collets arranged side-by-side in a straight rowfor supporting and moving successive sets of individual capsule shellswith their open-ends forward in timed relation from a work station to acorresponding parallel row of joiner blocks, characterized by a lightbeam projected on a line parallel to the joiner blocks across the pathof the conveyed capsule parts, photosensor means for scanning the lightbeam, control means for activating the photosensor means during apredetermined time segment such that the light beam bypasses a leadingedge of advancing standard-length capsule parts but is blocked andprevented from being scanned by the intervention of any over-lengthcapsule parts, and means responsive-t0 the scanning means for signallingthe presence of any set of capsule parts thus found blocking the beam.

1. Apparatus for the quality control of hard shell pharmaceuticalcapsules having a set of collets arranged side-byside in a straight rowfor supporting and moving successive sets of individual capsule shellswith their open-ends forward in timed relation from a work station to acorresponding parallel row of joiner blocks, characterized by a lightbeam projected on a line parallel to the joiner blocks across the pathof the conveyed capsule parts, photosensor means for scanning the lightbeam, control means for activating the photosensor means during apredetermined time segment such that the light beam bypasses the leadingedge of advancing standard-length capsule parts but is blocked andprevented from being scanned by the intervention of any over-lengthcapsule parts, and means responsive to the scanning means for rejectingany set of capsule parts thus found blocking the beam.
 2. Apparatusaccording to claim 1 where the liGht beam is projected by means of firstand second reflecting mirrors.
 3. Apparatus according to claim 1 wherethe control means comprises an electrical switch operated by cam means.4. Apparatus according to claim 1 where the means responsive to thescanning means comprises a solenoid-driven gate for rejecting capsuleparts.
 5. The apparatus of claim 1 where the rejection means responsiveto the scanning means comprises time-delay signalling means. 6.Apparatus for the quality control of hard shell pharmaceutical capsuleshaving a set of collets arranged side-by-side in a straight row forsupporting and moving successive sets of individual capsule shells withtheir open-ends forward in timed relation from a work station to acorresponding parallel row of joiner blocks, characterized by a lightbeam projected on a line parallel to the joiner blocks across the pathof the conveyed capsule parts, photosensor means for scanning the lightbeam, control means for activating the photosensor means during apredetermined time segment such that the light beam bypasses a leadingedge of advancing standard-length capsule parts but is blocked andprevented from being scanned by the intervention of any over-lengthcapsule parts, and means responsive to the scanning means for signallingthe presence of any set of capsule parts thus found blocking the beam.